The present invention generally relates to an endo file for dental endodontic treatment. More particularly, the present invention relates to an improved endo file for dental endodontic treatment, which includes a head portion connected to a hand piece, a tissue removing portion for removing a nerve of a tooth, and a stress dispersion portion provided between the head portion and the tissue removing portion and having a horizontal penetration hole, wherein the horizontal penetration hole of the stress dispersion portion is configured in various shapes so that the horizontal penetration hole can efficiently disperse torque that is transferred to an end of the endo file during a rotation of the endo file, without allowing concentration of the torque on a specific portion, whereby endo file breakage is minimized during use.
In general, an endo file is a medical tool for removing a nerve of a tooth, wherein the endo file is inserted into an inside of root canal of a tooth lesion for removing a nerve and/or diseased tissue. The endo file is made of an elastic material so as to be bent in response to a shape of a tooth.
The endo file is widely used in dental clinics across the world, wherein the endo file is mounted to a hand piece that rotates automatically by pneumatic power or electric motor.
FIG. 1 is a view showing a conventional endo file 1 described above.
The conventional endo file 1 includes: a head portion 20 detachably coupled to a hand piece 10; a tissue removing portion 30 at a lower part of the head portion 20 for removing a nerve of a tooth; and a connection portion 40 provided between the head portion 20 and the tissue removing portion 30 and functioning as a shape transition part.
According to the conventional endo file 1, when the head portion 20 that is detachably coupled to the hand piece 10 rotates, torque generated during the rotation is transmitted to the tissue removing portion 30, and the tissue removing portion 30 rotates. Thus, endodontic treatment is performed by removing a nerve, a blood vessel, and tissue of a tooth lesion (not shown) using the tissue removing portion 30. In a process of the endodontic treatment, the tissue removing portion of the conventional endo file 1 moves in and out of the root canal of the tooth repeatedly.
However, the conventional endo file 1 is often broken during use, namely during rotation. The breakage of the endo file 1 is caused by following reasons in the state of the tissue removing portion 30 being inserted into the root canal of the tooth: excessive stress occurs on the tissue removing portion 30 due to torque resistance of the nerve and the tissue when the tissue removing portion 30 rotates by the torque transmitted from the head portion 20; excessive stress is generated by rotation of the endo file in a portion of a root canal that is badly crooked; or sudden excessive stress occurs on some part of the endo file when the endo file is tightly caught in the root canal of the tooth.
Further, when treating a tooth located deep in a mouth, both the endo file and the hand piece coupled thereto should be put deep into the mouth. Here, for a patient who cannot open his or her mouth wide, it is highly possible that the tissue removing portion is badly bent and is broken due to a disadvantage of the conventional endo file configured such that the connection portion 40 thereof has very low elasticity in bending.
In particular, breakage or fracture of the endo file usually occurs at a certain section away from an end of the tissue removing portion 30, for example, at a location that is 1˜3 mm away from the end. However, it is not easy to modify the shape of the tissue removing portion 30 for removing a nerve and a blood vessel.
As a document of a related art relating to breakage of the conventional endo file, Korean Patent No. 10-1011695 discloses “Endo file for dental endodontic treatment”.
The endo file for dental endodontic treatment according to the above-mentioned related art is configured to be capable of easily removing a fragment of the endo file even when the end of the endo file is broken during the endodontic treatment. The endo file according to the related art includes: a tissue removing portion inserted into the inside of root canal of a tooth for removing a nerve and a blood vessel; and a connection portion provided on the tissue removing portion, wherein even when the tissue removing portion is broken due to repetitive use, the connection portion connects an upper part and a lower part of the fractured tissue removing portion together so that the lower part of the fractured tissue removing portion can be removed, along with the upper part, from the tooth.
The endo file for dental endodontic treatment according to the related art is advantageous in that it is possible to predict when a fracture of the tissue removing portion may occur due to repetitive use. Another advantage of the endo file according to the related art resides in that it is possible to prevent a fragment of the fractured tissue removing portion from being caught in the patient's tooth by easily removing an end of the fractured endo file from the tooth.
However, the related art focuses on removing the fractured end of the endo file 1 after the endo file 1 is broken. The related art is not intended to prevent the endo file 1 breakage itself in advance.